Vaillant boiler f29 fault

The F29 fault code will appear on a Vaillant boiler’s display in the following cases:

  • The incoming gas is not creating sufficient pressure
  • There is a flue issue
  • The gas valve is not set up properly or needs to be replaced
  • The burner is contaminated or blocked by debris
  • The electrode or ignition lead are damaged

These factors have just one consequence: there is no flame during operation.